1. Field of the Invention
The present invention relates to a locking mechanism for a rotary electric actuator intended for the formation of the shed on a loom, in particular for the control of the harness threads of a Jacquard-type weaving mechanism or of heddle frames of a loom provided with a dobby. The invention also relates to a weaving mechanism and to a weaving loom provided with such a mechanism.
2. Description of the Related Art
In Jacquard-type weaving mechanisms it is known to drive, in opposition of phases, two frames each of which is provided with a multiplicity of horizontal griffes or knifes appropriate for the vertical movement of hooks connected to the harness threads by a pulley or lifting mechanism. Mechanical or electromechanical devices are provided to immobilize these hooks along their vertical movement. This type of mechanism requires considerable power to operate the frames of the griffes, being this power supplied by the driving shaft of the loom, which leads to an oversizing of such a loom.
It is also known to use a rotary motor such as a stepping motor or a servomotor to linearly control a twine belonging to a loom.
A loom is not in constant operation, in order to be stopped at the end of the job or for the maintenance operations. Classically, looms are provided with a safety stop. In view of the foregoing reasons, it is beneficial to provide a locking mechanism to immobilize the rotary actuators, that is to say, the electric motors controlling the pulleys, so that in its shut-off position the loom maintains its off-position which would allow a rapid restart without any defects in the weft of the fabric being manufactured. In view of the large number of actuators belonging to a weaving mechanism, the associated locking mechanism must be compact and of simple construction in order to offer a low cost and great reliability. Further, the power consumption of a locking mechanism must be as low as possible in order not to originate very high operating costs.